Engine performance and reliability are key to a successful day fishing or boating. High-rpm operation and constant exposure to water, however, invite engine wear and formation of rust and corrosion, reducing engine performance and life. AMSOIL 25W-40 Synthetic Blend Marine Engine Oil guards against wear while delivering excellent protection against rust and corrosion. It is Warranty Secure® and will not void your marine engine's warranty.

AMSOIL 25W-40 Synthetic-Blend Marine Engine Oil can be used in gasoline-fueled four-stroke inboards, outboards, inboard/outboards and personal watercraft that require any of the specifications listed below, including those made by Mercury* and Mercruiser*.

Product Application Specs

• API SM
• NMMA FC-W Catalyst Compatible

Product DescriptionProtects Against Wear: Marine engines operate under high loads and rpm for extended periods. On average, a marine engine powering a boat 30 mph runs at about 5,000 rpm. In contrast, an automotive engine powering a car 60 mph runs at about 2,000 rpm. Higher stress causes traditional automotive oils to break down and lose viscosity. AMSOIL 25W-40 Synthetic Blend Marine Engine Oil is designed with excellent shear stability to deliver a consistent lubricating film. It helps guard engine components from wear for maximum life.

Excellent Anti-Rust Performance
Marine engines are prone to rust and corrosion due to constant exposure to humid, wet environments. Rust on engine parts acts like sandpaper, scouring bearings, the cylinder wall, piston rings and other components, while aluminum pistons and other parts can corrode. Rust and corrosion reduce engine power and eventually cause catastrophic failure.

Good rust protection is not natural to motor oil; it comes only by design. AMSOIL 25W-40 Synthetic Blend Marine Engine Oil is fortified with potent inhibitors that guard against damaging rust and corrosion.

* All trademarked names and images are the property of their respective owners and may be registered marks in some countries. No affiliation or endorsement claim, express or implied, is made by their use. All products advertised here are AMSOIL-engineered for use in the applications shown.

Service Life
Four-stroke outboard motors and personal watercraft: Due to potential fuel dilution or water contamination, change oil at the engine or watercraft manufacturer-recommended interval. Inboard and I/O applications: Change oil at two times the engine manufacturer-recommended interval, or once a year, whichever comes first.

HEALTH & SAFETY
This product is not expected to cause health concerns when used for the intended application and according to the recommendations in the Material Safety Data Sheet (MSDS).